Bioaccessibility of pesticides and polychlorinated biphenyls from house dust: in-vitro methods and human exposure assessment.

Semi-volatile chemicals like pesticides and polychlorinated biphenyls (PCB) tend to accumulate in house dust. This may result in residues of some parts per million (p.p.

Initiation of radical chain reactions of thiol compounds and alkenes without any added initiator: thiol-catalyzed cis/trans isomerization of methyl oleate.

A kinetic study of the dodecanethiol-catalyzed cis/trans isomerization of methyl oleate (cis-2) without added initiator was performed by focusing on the initiation of the radical chain reaction. The reaction orders of the rate of isomerization were 2 and 0.5 for 1 and cis-2, respectively, and an overall kinetic isotope effect k(H)/k(D) of 2.

A controlled challenge study on di(2-ethylhexyl) phthalate (DEHP) in house dust and the immune response in human nasal mucosa of allergic subjects.

Background: Few studies have yet addressed the effects of di(2-ethylhexyl) phthalate (DEHP) in house dust on human nasal mucosa.

Objectives: We investigated the effects of house dust containing DEHP on nasal mucosa of healthy and house dust mite (HDM)-allergic subjects in a short-term exposure setting.

Methods: We challenged 16 healthy and 16 HDM-allergic subjects for 3 hr with house dust at a concentration of 300 microg/m(3) containing either low (0.

Reference values for metabolites of pyrethroid and organophosphorous insecticides in urine for human biomonitoring in environmental medicine.

Pesticides are widely used throughout the world in agriculture to protect crops, and in public health to control diseases transmitted by vectors or intermediate hosts. After the prohibition of organochlorines, such as DDT, today mainly pyrethroids and organophosphorous insecticides are used. With reliable and sensitive analytical methods for detecting metabolites of organophosphorous and pyrethroid insecticides in urinary specimens of the general population several studies have been published on internal exposure to these insecticides of the population in Germany.